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本文是一篇关于记忆和遗忘方面的心理学的文章。

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In thinking about the evolution of memory together with all its possible aspects, it is helpful to consider what would happen if memories failed to fade. Forgetting clearly aids orientation in time, since old memories weaken and the new tend to stand out, providing clues for inferring duration. Without forgetting, adaptive ability would suffer, for example, learned behavior that might have been correct a decade ago may no longer be. Cases are recorded of people who (by ordinary standards) forgot so little that their everyday activities were full of confusion. Thus forgetting seems to serve that survival of the individual and the species. Another line of thought assumes a memory storage system of limited capacity that provides adaptive flexibility specifically through forgetting. In this view, continual adjustments are made between learning or memory storage (input) and forgetting (output). Indeed, there is evidence that the rate at which individuals forgets is directly related to how much they have learned. Such data offer gross support of contemporary models of memory that assume an input-output balance.
在思考记忆的进化过程及其他相关方面时，考虑下面这个问题是很有益处的，即，如果记忆不能渐渐消失将会出现什么情形。遗忘明显有助于时间的定位，因为旧的记忆淡化了，使新的记忆清晰醒目，为推断某事的持续时间提供了线索。没有遗忘，适应性能力就会受损；例如，十年前所学的正确行为现在也许不再被认为是正确的。案例记载了这样一些人，他们（按一般人的标准）忘记的事情太少以至于日常生活充满了困惑。因此，遗忘似乎有助于个人以及人类的生存。 另一条思路假设人的记忆存储系统储量有限，它专门通过遗忘来提供适应之灵活性。依此观点，学习或记忆储存（输入）与遗忘（输出）之间始终在不断地调节。的确，有证据显示个人遗忘的比率与他们学得的知识量的多少直接相关。这样的数据为认为输入—输出持衡的当代记忆模式提供了总体上的支持。